Even if there actually is no SIMD optimized version of the
width==2 cases, luma function for SIMD still needs to handle
it by calling McCopyWidthEq2_c for these cases.
This simplifies the UT code a little, and makes sure that
those codepaths are tested properly.
This speeds up the compile time from 21.3 to 2.6 seconds
for the MC test files.
This makes it slightly harder to see exactly which test
failed on a quick glance, but it makes the overall structure of
the unit test output more manageable and readable, by reducing
the number of tests from 1300 to 430.
This makes sure we don't accidentally return the same sequence
of random numbers multiple times within one test (which would
be very non-random).
Every time srand(time()) is called, the pseudo random number
generator is initialized to the same value (as long as time()
returned the same value).
By initializing the random number generator once and for all
before starting to run the unit tests, we are sure we don't
need to reinitialize it within all the tests and all the
functions that use random numbers.
This fixes occasional errors in MotionEstimateTest.
MotionEstimateTest was designed to allow the test to occasionally
not succeed - if it didn't succeed, it tried again, up to 100 times.
However, since the YUVPixelDataGenerator function reset the random
seed to time(), every attempt actually ran with the same random
data (as long as all 100 attempts ran within 1 second) - thus if
one attempt in MotionEstimateTest failed, all 100 of them would
fail. If the utility functions don't touch the random seed,
this is not an issue.
